Montana Department of Transportation

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Fuel Taxes


Each year the Montana Department of Transportation (MDT) is required to determine fuel tax allocations distributed to Montana's cities, counties, and consolidated city-county governments set forth in 15-70-101 MCA, as amended.

One of the factors used to calculate the amount allocated to each local entity is road mileage. Mileages for counties consist of any road exclusive of the National Highway and Primary Systems within the county boundary and outside any incorporated city limits that meet the criteria of "open to public travel" as stated below:

Open to Public Travel is defined as a segment of road available for public use except during periods of extreme weather or emergency conditions, passable by a 2-wheel drive passenger car and open to the general public. Restrictions include; primitive trails, driveway to a single residence, field access roads, parking lots, restrictive gates, orange markings on posts, or "No Trespassing" signs ( MCA 45-6-201).

MDT conducts field inventories yearly to collect new road coordinates using GPS technology and to ensure the roads are "open to public travel".

Our database is continuously updated. In addition to the annual mileage certification returns from the cities and counties, results from field reviews and the discovery of errors can have an effect on the mileage numbers from year to year.

Official fuel tax roads, mileages and maps are held in the office of MDT. For requests or comments please or contact him at 406-444-6103.